Intermittent Limp Mode and No Starts

[stephen_trainor]

Hi all,

I have been having two distinct issues with my citroen relay van for quite some time now. Both issues seem to be worse on particular days with no obvious signs as to why.

1. The first issue is that the van fails to start when turning the key. Sometimes there is a click and sometimes nothing. I have checked the battery and even replaced it but to no avail. I also replaced the ground strap. Sometimes it takes 40 mins to start and sometimes it starts on a dime. I have had this looked at with multiple mechanics and they reckon the starter is just fine. After doing some searching I am being told this may be e gearbox to chassis earth strap issue so I am having that changed now. Also, one day when trying to start in gear which I did accidentally, one of the large fuses which I believe was the starter mega fuse over the battery blew which was quite concerning. I also had the starter relay replaced. After this I am going to dig around the enginer fuse box in more detail and then it will be onto wiring but just wanted to see if I am on the right track here.

2. The second issue is that the van goes into limp mode intermittently. I does seem to be when I put the foot down on the throttle but not always. Some days this never happens and sometimes it happens on motorways or when cruising at a low speed just after turning vehicle on.

I did a scan for fault codes recently and I got the following:

P0234 - Turbocharger, engine boost condition - limit exceeded
U1701(87) Archive (Inactive)
U0426(31) - Invalid Data received - immobilizer control module

I am planning to have a look at the actual pressure vs ideal pressure when accelerating using my OBD dongle but haven't done this before so will be a little bit of trial and error. I also read online that changing the boost pressure valve can solve this. I am not sure if I should just go ahead and buy this though as it's expensive and I don't want to change it if it's not necessary.

I have spent a lot of money trying to fix these issues to no avail and given the fact that this is a campervan that I converted myself it is quite valuable so I want to get it working again so I can enjoy it.

Any help would be highly appreciated.

Thanks,

Stephen

[Paul-R]

How many miles has the vehicle done? How old is it?

[parnell]

Which OBD dongle do you have ? I would recommend you to get diagbox working on a laptop if you can as that will provide a great deal of detail as to when and hopefully why those fault codes arose. I got a cloned full chip obd dongle as well as some rubbish Chinese version hacked - the second part I got a solution to via easydiagnostics.co.uk who provided a much better version of the diagbox software. Best of luck